Deconstructing Actavis v Eli Lilly

The Supreme Court's decision in Actavis v Eli Lilly [2017] UKSC 48 has changed the way that the UK courts will determine the extent of protection of a patent's claim. Prior to this decision, since the House of Lords' decision in Catnic Components v Hill [1982] RPC 183 the UK courts has used "purposive construction" in order to establish the scope of a patent's claim.

As famously explained by Lord Hoffmann in the seminal decision of the House of Lords in Kirin Amgen v Hoechst Marion Roussel [2005] RPC 9 the crux of purposive construction is to determine "what the person skilled in the art would have understood the patentee to be using the language of the claim to mean".